Справочник Пользователя для Emerson 308014EN

Скачать
Страница из 166
6-5
Rosemount Tank Radar REX
Chapter 6 The Field Communication
Installation Manual
308014EN, Edition 4
May 2013
6.5
Redundancy
In order to reduce the risk of communication failure between the 
TankMaster and the units connected to the TRL/2 fieldbus, two FCUs 
can be connected to run in parallel to provide automatic redundancy. The 
FCUs are connected with an extra cable allowing them to communicate. 
The inactive FCU constantly checks if the connected FCU is active. If the 
active FCU fails, it signals to the backup FCU to take over. Then the 
backup FCU immediately switches to an active state. It is also possible 
to use up to four TankMaster PC:s connected via different Group Buses.
Redundant FCU:s.
Two FCU:s can be connected 
in parallel. One of them is con-
figured as the primary FCU and 
the other as backup. The pri-
mary FCU is active. The 
backup FCU listens to the com-
munication on the Field Bus 
and automatically takes over 
the communication without any 
action from the operator if the 
primary FCU fails.
Double FCU:s and 
workstations.
With two FCU:s and two Tank-
Master workstations a com-
plete redundancy from control 
room to RTG is achieved.
FCU_redundant.eps
FCU_redundant_workstation.eps